ok, these parts sound considerably better. i think the compression pedal is buffering the signal a little, which is helping the limiter even when it's off. i also plugged it into a regulated power supply, which may have minimized any background. and i turned the low eq pot down a bit on the way in. it's still buzzing mildly, but the clippiness is gone.

i'm sleepy. but i have every reason to think this'll be done tomorrow.